It actually looks like you're missing parts 12 AND 10. There's a lower hard rubber slider to keep the chain off the metal swingarm and theres an upper thinner plastic piece to keep your fingers/pants leg/etc from getting caught in the chain. Both are important.

FYI a bike needs the chain lubed every week if used, or every 500~700 miles...

It also needs a tension adjustment every 1200~3000 miles or every 6 months or so, depends on the power of the bike, and what type of riding you do. If you don't lube the chain, it won't last more than 10k miles and will eventually snap like a rubber band, which may cause the rear to lock up and you going down.

Also it drastically reduces your sprocket life. Just make it good habit to lube the chain once a week. It takes less than 5 minutes. I get mine done in about 1 or 2 minutes. Adjusting chain tension usually takes me 7-15 minutes.

As someone who rides in the rain and never lubes my chain, I end up just buying a new chain every 6 months or whenever it needs to be replaced. I do check the tension which everyone should do as this is the primary cause when the chain flies off.

I never understand why people don't lube the chain. An x-ring chain costs like $120~200. A bottle of lube costs $2.80 and will take a total of maybe 30 minutes over the life of the chain. You'd be saving yourself $400 / year by spending 30 minutes and $2.80

Also, rear sprockets are 40 to 90 bucks, which under maintained chains chew up. If it's starting to fish hook it needs replacement soon or it will start slipping.

You could be saving so much more money if you just lube your chain. Having lived in Seattle and riding in the rain, my EX500 has been able to go up to 14,000 miles thus far without a chain or sprocket replacement, its still on the factory parts. At least spray it down during warmup every so often.

If you ever get 10k out of a sportbike chain you either never use more than 1/8th throttle, or don't know how to tell when you need a new chain. I would give most chain a max of 5k miles before the rear sprocket is toast, and replacing sprockets means replacing chains.

I regularly redline my bike, occasionally hit the revlimiter during hooligan activities, and do trackdays as well. The chain is at 8k miles and could easily last another 10k. My sprockets are still as good as the day I bought the bike...

If you're getting that little lifespan out of a chain and sprocket, you're doing something wrong - or just don't care about maintenance. I always get a good laugh out of people who think it's cool to ruin engine and drive components from being heavy handed and uncaring about making mechanical equipment last. That's just pissing away money. I ride my bike pretty hard, but still maintain it.

I wouldn't go low quality with spinny whirrly whip you in the back of the leg metal bits, lol.

I look after all bits of my bike. The only time I bring it in is for valve services, or other major engine work that doesn't involve the electronics. I can handle anything else, and probably the services too. I'd rather bring it in and have it serviced by someone who does it at least twice a month for a living. Also I find major engine services a huge timesink and headache to try to fit into my schedule somewhere, if I were to do it myself. Easier to drop it off for a weekend and forget about it until Monday - plus it will be done right the first time (hopefully).

Wow, so you're an ass to boot. I would love to see close up pictures of your front and rear sprockets and the air gap between the chain and rear sprocket to back up your claim. Chains do not last 18k miles, no matter how easy you are on them, and to make that claim is flat out false. Want to assume I'm heavy handed? Go ahead, thats also false. I took amazaing care of my stuff, but wear parts wear out.

Tension is set to 1.1 inches. A chain is done when you're starting to run out of room on the tensioner block. It stretches out pretty good the first couple thousand miles but will slow after that and won't really need any adjustment for a while.

As another redditor suggested to me, maybe you're buying a lower quality chain? A DID x-ring chain easily lasts over 10,000 miles.

You can't inspect a chain from 20 feet away while its going 40 mph. The CBR you posted is blurry and doesn't have a close of of either the chain or sprocket, so yes it may have the stock sprockets and they probably look like crap and need to be replaced.

Sorry it was the only good photo I had on me. Look, you're probably right and only can get < 10k out of a chain, but I guess it depends on what chain you're getting? Do you usually pick up O rings? I've never worn out a chain faster than 13k miles...

No its far from dangerous. Just lube it up good and if it's smooth don't sweat it. If it's so rusty it wants to kink then replace it.

Yeah this. The chain looks like it just has a bit of surface corrosion on it and it doesn't appear to be compromising the pins. If the rest of the chain looks like that I would just take a wire brush to it to clean off the rust and give it a good coating of lube, I would be very generous in covering the chain if it's going to sit.

I mean dangerous meaning it's not been taken care of & is going to snap at any point. Ever hear the saying about the weakest link in a chain? ;) All it takes is one of those little guys to come loose and it's going to cut your damned foot off.

Before you lube up this chain, I would clean it with some penetrating oil, just to break off all the rust. Get those little brush things and scrub that chain. Wipe the chain down till its dry, you dont want any oil being left behing and then go ahead and liberally apply chain lube/